The antonyms for the word "more demonstrated" can be "less proven," "uncertain," or "untested." When a theory or concept has not been extensively analyzed or evaluated, it cannot be considered as "more demonstrated." The term "less proven" characterizes a situation where there is limited evidence to support an idea or argument. Similarly, when there is no proof or evidence to support a claim, it is regarded as "uncertain." Lastly, when something has not undergone experimentation or analysis, it is defined as "untested." Therefore, it is essential to have adequate evidence and proof to establish a concept as "more demonstrated.